import java.util.Scanner;//1045: 【入门】判断能否构成三角形

public class Main1045 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int c = sc.nextInt();
        if (a + b > c && a + c > b && b + c > a) {
            System.out.println("Yes");
        } else {
            System.out.println("No");
        }
    }
}
